Current forming technology relies on high pressure, speed and complicated material flow pathways which produce a product lacking in quality. High pressure works the meat cells, the higher the pressure the more massaging or squeezing of the meat cells takes place. High speed combined with a complicated flow path massages and works the meat product, releasing myosin/actin from the cells causing the muscle fiber to bind together and contract (protein bind). The contraction takes place during high heat application as in cooking. The action of the meat fiber is to contract in length, this contraction combined with protein bind not only shortens the muscle fiber which if not controlled causes odd cook shapes but a rubber like texture with a tough bite.
In muscle, actin is the major component of thin filaments, which together with the motor protein myosin (which forms thick filaments), are arranged into actomyosin myofibrils. These fibrils comprise the mechanism of muscle contraction. Using the hydrolysis of ATP for energy, myosin heads undergo a cycle during which they attach to thin filaments, exerting a tension, and then depending on the load, perform a power stroke that causes the thin filaments to slide past, shortening the muscle.
Muscle fibril structure is measured from micrometers to several millimeters in length. These fibril structures are bundled together to form muscles. Myofibril proteins are the largest group and probably more is known about these proteins than any other. In muscle cells actin is the scaffold on which myosin proteins generate force to support muscle contraction. Myosin is the major protein that is extracted from the muscle cells by mechanical means.
An important purpose of tumbling and massaging is to solubiliize and extract myofibril proteins to produce a protein exudate on the surface of the meat. The exudates bind the formed pieces together upon heating. Binding strength also increases with increased massaging or blending time. This is due to increased exudate formation on the surface of the meat. Crude myosin extraction is increased with increased blending time.
Grinding/chopping utilizes the concept of rupturing the cell to release protein. This mechanical chopping or shearing takes place at the shear/fill plate hole. This process extracts myosin from muscle cells.
Mixing, utilizes friction and kinetic energy to release protein exudate. Fill hole shape and spacing can cause dead spots and turbulence in the meat flow. This change of direction is a form of mixing and massaging. This is another process, which extracts myosin from muscle cells.
Massaging takes place almost anywhere meat comes in contact with processing equipment and is moved or has a change of direction via pressure. This is also a procedure which involves extracting myosin from muscle cells.